1. Field of the Invention
The invention relates to a power adapter and, more particularly, to a power adapter which can stop providing an output voltage in time.
2. Description of the Related Art
As a portable electronic device is widely used nowadays, a power adapter for providing power is also widely used. When the power adapter is not connected to the electronic device, the power consumption of the power adapter should be taken into account.
Moreover, if the power adapter continuously outputs a voltage when it is not connected to a load, when the power adapter is connected to the electronic device, current density may increase due to the small contact area of connectors and sparkle affection may generate. The sparkle affection may hurt the user and damage the connector.
In conventional technology, an electronic device as a load can transmit a signal to the power adapter to indicate different working states (such as booting, standby, sleep or normal operation states) of the electronic device connected to power adapter. However, the power adapter should cooperate with the electronic device which can provide the indicating signal, and the power adapter only gets the working state of the electronic device, which does not include a connecting state of the electronic device and the power adapter.